Normal and Abnormal Glycogen Molecules (IMAGE) Indiana University School of Medicine Caption Electron microscopy images demonstrate how glycogen molecules (left) become structurally abnormal (right) when excessive levels of phosphate are attached due to a mutation in the lafora gene. Credit Indiana University School of Medicine Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.